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2008-5-20IVOA Interoperability Meeting, Trieste2 China-VO Chinese Virtual Observatory (China-VO) is the national VO project in China initiated in 2002 by Chinese astronomical community led by National Astronomical Observatories, Chinese Academy of Sciences. It focuses its research and development on VO science and applications. R&D focuses: –China-VO Platform –Unified Access to On-line Astronomical Resources and Services –VO-ready Projects and Facilities –VO-based Astronomical Research Activities –VO-based Public Education

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2008-5-20IVOA Interoperability Meeting, Trieste5 First Science Paper from China-VO SDSS DR5 photometric data were searched for new Milky Way companions or substructures in the Galactic halo. Data analysis procedures were based on the VO-DAS. Five candidates are identified as over-dense faint stellar sources that have color-magnitude diagrams similar to those of known globular clusters, or dwarf spherical galaxies. – Liu et al., 2008, A&A)

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2008-5-20IVOA Interoperability Meeting, Trieste8 An introduction to MATLAB MATLAB is a popular numerical computation software used in variant fields. It provides dozens of toolboxes for different purposes, e.g. statistics, pattern recognizing, optimizing, neural networks etc., as well as a number of way to access data from either local or remote sites. It also offers visualizations by flexible 2D and 3D graphics routines. It supports Java, C, and Fortran as well as its own M-language. It is available of accessing URL resources and parsing XML, which is necessary for embedding web service. In its latest release, refined parallel computation is ready. We conclude that MATLAB is one of the best platforms on which astronomical data mining tools can be developed

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2008-5-20IVOA Interoperability Meeting, Trieste10 VO utilities in AstroBox VOTable access and conversion –integrate STILS package PLASTIC availability –embed a Java subroutine to connect to PLASTIC Hub through which to exchange data and messages with third party applications, e. g. Aladin and TOPCAT. –SAMP support next... VO-DAS client interface –embed a VO-DAS command line client to send an ADQL to VO-DAS server and wait for query result –It is also capable for asynchronous query, which can access millions of rows of data (on going)

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2008-5-20IVOA Interoperability Meeting, Trieste12 Other functions High level functions aiming at specific research topics, most of which currently are Milky Way related –Kurucz stellar model –Gerardi stellar population model –isochrone fitting the stellar population –Galactic star count model with disk and halo components –Chemical evolution model for stellar population (on going) Most common used utilities –Monte Carlo methods –coordination transformations –magnitude system transformations

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2008-5-20IVOA Interoperability Meeting, Trieste17 Demo 5 Parallel computation –fitting a 9-parameter star count model in a 8-core server –faster than that in a single-core computer at a factor of ~8.

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2008-5-20IVOA Interoperability Meeting, Trieste18 Future works Release as a tool to the community Extend cosmology methods Establish a distributed parallel computation environment Deploy an on-line data mining service